No one wants a festival of ideas to turn into a cozy chat among like-minded friends. That’s pointless.

But also utterly pointless is the notion that Steve Bannon, President Trump’s former chief strategist, might have something new or valuable to offer.

That’s why it was a thoroughly lousy idea for the New Yorker magazine to offer a high-profile perch — an onstage interview by top editor David Remnick — at next month’s annual festival to the deposed Svengali.

There is nothing more to learn from Bannon about his particular brand of populism, with its blatant overlay of white supremacy.

While we’re at it, there is also nothing more to learn from the die-hard Trump voters in what I’ve called the Endless Diner Series — the media’s recidivistic journeys to the supposed heartland to hear what we’ve heard a thousand times before about blind loyalty in the face of all reason.

There is also nothing more to learn from proven dissemblers, like Kellyanne Conway, who keep being invited onto the top news shows to shamelessly spout whatever falsehood serves the Trumpian moment.

Yes, it’s time, well past time, to stop lending the media’s biggest and most prestigious platforms to this crowd of racists and liars.

Shut them down — not because of ideology or politics, but because there is no news value there.

Under fire, Remnick, who deservedly is one of the country’s most respected journalists, figured this out late Monday — sort of — and withdrew the magazine’s invitation. (He said, however, that he’d still be open to doing the Bannon interview in some other less public setting, presumably one that doesn’t involve paying an honorarium for the privilege of hearing the former Breitbart News chairman promote himself and his offensive ideas.)

“I’ve changed my mind,” Remnick wrote in a memo to staff. He may not have had a lot of choice, as one after another of the festival’s celebrity invitees — including Jim Carrey and Judd Apatow — began to bail out in protest, and as New Yorker writers took to Twitter to make their displeasure known.

After the reversal, New Yorker staffer Adam Davidson made the unassailable point that Remnick has earned the right to screw up once in while. And that he deserves credit for listening to the protests: “He spent all day today on the phone with writers and staffers telling him he’s wrong. He listened.”

That’s good. Remnick also deserves credit for something far more significant: Giving Ronan Farrow’s stellar investigative work on Harvey Weinstein a safe harbor last year after NBC failed to provide adequate support. (The reporting went on to win a Pulitzer Prize for Public Service.)

What happened with Bannon and the New Yorker Festival, though it may appear to be just another digital-age dust-up, is part of a much deeper media problem: the normalization of people and ideas that deserve only scorn — all done in the name of understanding and challenging them.

Author Roxane Gay offered an unvarnished view on Twitter: Inviting Bannon “demonstrates how the intellectual class doesn’t truly understand racism or xenophobia. They treat it like an intellectual project, where perhaps if we ask ‘hard questions’ and bandy about ‘controversial’ ideas, good work is being done.”

Remnick said that interviewing Bannon wasn’t the same as endorsing him. He clearly planned to make this a tough, revelatory session. But what’s left to reveal?

Sadly, even the withdrawal of the festival invitation accomplishes Bannon’s purposes.

He immediately branded Remnick “gutless” and will manage to tour behind this episode for weeks. Perfect timing, really, given that Oscar-winning documentary filmmaker Errol Morris this week is launching “American Dharma,” a combative interview with Bannon, at the Venice Film Festival and in Toronto.

On its own, the New Yorker’s blunder — for it certainly is that — may not matter much. But as part of a larger pattern of providing legitimacy and normality, it’s worse than regrettable.

It would be heartening to believe that something might be learned from this episode. But the news media, even at its highest and most admirable levels, doesn’t seem to get the point.

Challenging the likes of Bannon, or pushing back against the likes of Conway, only makes these figures into folk heroes, bravely telling their would-be truths to a corrupt media elite.

It would be better to stop obsessively looking back at how Trump came to be, turning 2016 this way and that like some dark prism.

We all understand by now the unsavory blend of factors — including a hefty serving of straight-up racism — that brought him to power.

There’s nothing more to learn. But, in elevating these ideas and their practitioners again and again, there’s plenty more still to lose.